leetcode Remove Duplicates from Sorted Array II 2.18 难度系数2

Question:

Follow up for "Remove Duplicates":

What if duplicates are allowed at most twice?

For example,

Given sorted array A = 

[1,1,1,2,2,3]

,

Your function should return length = 

5

, and A is now 

[1,1,2,2,3]

.

public int removeDuplicates(int[] A) {
if (A.length <= 2) {
return A.length;
}
int index = 2;

for (int i = 2; i < A.length; i++){
if (A[i]!=A[index-2]) {
A[index++] = A[i];
}
}

return index;
}